Where Did My Child Support Go?

Once you divorce, or have a separation agreement and are getting a regular child support, it helps, but it doesn't pay all the bills, at least not in our case. We are living on a measly monthly amount, thank goodness I work ! When we got our divorce, my child support gets paid by him mailing in the check to the government, and they, in turn, make record of the payment and forward the money on to me. That works, and everybody's fine with how it's done, however, for the past 3 months, there has been no child support. Granted, we don't get much, because when it was time for the amount he was to pay, I settled for a little less than what he was supposed to pay. I thought that I was being nice to him, since he is self-employed and doesn't always make the same amount each month. However, due to an accident, he was out of work for a little while. Now that he is working again, he is paying his other bills, but nothing for us. How does he think that we are supposed to make ends meet with less money? Money that we are supposed to be given. It takes both parents in this day and age to raise a child, especially with a teenager, things are a quite a bit more expensive. I am now wondering when my next child support payment will be coming in and pondering at the thought of how to proceed with this matter. I just don't understand why he thinks it's ok to pay all his bills and forget about his daughter's needs.